// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/renderer_host/render_widget_helper.h"

#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/lazy_instance.h"
#include "base/posix/eintr_wrapper.h"
#include "base/threading/thread.h"
#include "base/threading/thread_restrictions.h"
#include "content/browser/dom_storage/session_storage_namespace_impl.h"
#include "content/browser/frame_host/render_frame_host_impl.h"
#include "content/browser/loader/resource_dispatcher_host_impl.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/browser/renderer_host/render_view_host_impl.h"
#include "content/common/view_messages.h"

namespace content {
namespace {

    typedef std::map<int, RenderWidgetHelper*> WidgetHelperMap;
    base::LazyInstance<WidgetHelperMap> g_widget_helpers = LAZY_INSTANCE_INITIALIZER;

    void AddWidgetHelper(int render_process_id,
        const scoped_refptr<RenderWidgetHelper>& widget_helper)
    {
        DCHECK_CURRENTLY_ON(BrowserThread::IO);
        // We don't care if RenderWidgetHelpers overwrite an existing process_id. Just
        // want this to be up to date.
        g_widget_helpers.Get()[render_process_id] = widget_helper.get();
    }

} // namespace

RenderWidgetHelper::RenderWidgetHelper()
    : render_process_id_(-1)
    , resource_dispatcher_host_(NULL)
{
}

RenderWidgetHelper::~RenderWidgetHelper()
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);

    // Delete this RWH from the map if it is found.
    WidgetHelperMap& widget_map = g_widget_helpers.Get();
    WidgetHelperMap::iterator it = widget_map.find(render_process_id_);
    if (it != widget_map.end() && it->second == this)
        widget_map.erase(it);
}

void RenderWidgetHelper::Init(
    int render_process_id,
    ResourceDispatcherHostImpl* resource_dispatcher_host)
{
    render_process_id_ = render_process_id;
    resource_dispatcher_host_ = resource_dispatcher_host;

    BrowserThread::PostTask(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&AddWidgetHelper,
            render_process_id_, make_scoped_refptr(this)));
}

int RenderWidgetHelper::GetNextRoutingID()
{
    return next_routing_id_.GetNext() + 1;
}

// static
RenderWidgetHelper* RenderWidgetHelper::FromProcessHostID(
    int render_process_host_id)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    WidgetHelperMap::const_iterator ci = g_widget_helpers.Get().find(
        render_process_host_id);
    return (ci == g_widget_helpers.Get().end()) ? NULL : ci->second;
}

void RenderWidgetHelper::ResumeDeferredNavigation(
    const GlobalRequestID& request_id)
{
    BrowserThread::PostTask(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&RenderWidgetHelper::OnResumeDeferredNavigation,
            this,
            request_id));
}

void RenderWidgetHelper::OnResumeDeferredNavigation(
    const GlobalRequestID& request_id)
{
    resource_dispatcher_host_->ResumeDeferredNavigation(request_id);
}

void RenderWidgetHelper::CreateNewWindow(
    mojom::CreateNewWindowParamsPtr params,
    bool no_javascript_access,
    int32_t* render_view_route_id,
    int32_t* main_frame_route_id,
    int32_t* main_frame_widget_route_id,
    SessionStorageNamespace* session_storage_namespace)
{
    if (params->opener_suppressed || no_javascript_access) {
        // If the opener is supppressed or script access is disallowed, we should
        // open the window in a new BrowsingInstance, and thus a new process. That
        // means the current renderer process will not be able to route messages to
        // it. Because of this, we will immediately show and navigate the window
        // in OnCreateNewWindowOnUI, using the params provided here.
        *render_view_route_id = MSG_ROUTING_NONE;
        *main_frame_route_id = MSG_ROUTING_NONE;
        *main_frame_widget_route_id = MSG_ROUTING_NONE;
    } else {
        *render_view_route_id = GetNextRoutingID();
        *main_frame_route_id = GetNextRoutingID();
        // TODO(avi): When RenderViewHostImpl has-a RenderWidgetHostImpl, this
        // should be updated to give the widget a distinct routing ID.
        // https://crbug.com/545684
        *main_frame_widget_route_id = *render_view_route_id;
        // Block resource requests until the frame is created, since the HWND might
        // be needed if a response ends up creating a plugin. We'll only have a
        // single frame at this point. These requests will be resumed either in
        // WebContentsImpl::CreateNewWindow or RenderFrameHost::Init.
        resource_dispatcher_host_->BlockRequestsForRoute(
            GlobalFrameRoutingId(render_process_id_, *main_frame_route_id));
    }

    BrowserThread::PostTask(
        BrowserThread::UI, FROM_HERE,
        base::Bind(&RenderWidgetHelper::OnCreateNewWindowOnUI, this,
            base::Passed(&params), *render_view_route_id,
            *main_frame_route_id, *main_frame_widget_route_id,
            base::RetainedRef(session_storage_namespace)));
}

void RenderWidgetHelper::OnCreateNewWindowOnUI(
    mojom::CreateNewWindowParamsPtr params,
    int32_t render_view_route_id,
    int32_t main_frame_route_id,
    int32_t main_frame_widget_route_id,
    SessionStorageNamespace* session_storage_namespace)
{
    RenderFrameHostImpl* opener = RenderFrameHostImpl::FromID(
        render_process_id_, params->opener_render_frame_id);
    if (opener && opener->IsRenderFrameLive()) {
        opener->OnCreateNewWindow(render_view_route_id, main_frame_route_id,
            main_frame_widget_route_id, *params,
            session_storage_namespace);
    }

    // If we did not create a WebContents to host the renderer-created
    // RenderFrame/RenderView/RenderWidget objects, destroy them.
    RenderProcessHost* rph = RenderProcessHost::FromID(render_process_id_);
    if (main_frame_route_id != MSG_ROUTING_NONE && rph != nullptr) {
        bool succeeded = RenderWidgetHost::FromID(render_process_id_,
                             main_frame_widget_route_id)
            != nullptr;
        if (!succeeded) {
            DCHECK(!RenderFrameHost::FromID(render_process_id_, main_frame_route_id));
            DCHECK(!RenderViewHost::FromID(render_process_id_, render_view_route_id));

            rph->Send(new ViewMsg_Close(render_view_route_id));
        } else {
            // If a RWH was created, there should also be an RFH and RVH.
            DCHECK(RenderFrameHost::FromID(render_process_id_, main_frame_route_id));
            DCHECK(RenderViewHost::FromID(render_process_id_, render_view_route_id));
        }
    }
}

void RenderWidgetHelper::CreateNewWidget(int opener_id,
    blink::WebPopupType popup_type,
    int* route_id)
{
    *route_id = GetNextRoutingID();
    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
        base::Bind(&RenderWidgetHelper::OnCreateWidgetOnUI,
            this, opener_id, *route_id, popup_type));
}

void RenderWidgetHelper::CreateNewFullscreenWidget(int opener_id,
    int* route_id)
{
    *route_id = GetNextRoutingID();
    BrowserThread::PostTask(
        BrowserThread::UI, FROM_HERE,
        base::Bind(&RenderWidgetHelper::OnCreateFullscreenWidgetOnUI, this,
            opener_id, *route_id));
}

void RenderWidgetHelper::OnCreateWidgetOnUI(int32_t opener_id,
    int32_t route_id,
    blink::WebPopupType popup_type)
{
    RenderViewHostImpl* host = RenderViewHostImpl::FromID(
        render_process_id_, opener_id);
    if (host)
        host->CreateNewWidget(route_id, popup_type);
}

void RenderWidgetHelper::OnCreateFullscreenWidgetOnUI(int32_t opener_id,
    int32_t route_id)
{
    RenderViewHostImpl* host = RenderViewHostImpl::FromID(
        render_process_id_, opener_id);
    if (host)
        host->CreateNewFullscreenWidget(route_id);
}

} // namespace content
